| Variable | 7–3 Years before(n = 393) | 3–1 Years before(n = 228) | 1–0 Years before(n = 86) | 0–1 Years after(n = 76) | 1–3 Years after(n = 146) | 3–7 Years after(n = 158) | Sig.* | Test of non-linearity† |
| Participation rate (%) | 54.6 | 50.8 | 45.3 | 40.5 | 47.1 | 44.9 | p = 0.003 | – |
| Female gender (%) | 66.2 | 75.0 | 66.3 | 59.2 | 67.1 | 63.9 | p = 0.091 | – |
| Education (%) | p = 0.322 | – | ||||||
| Primary | 37.7 | 32.5 | 24.4 | 46.1 | 37.0 | 36.7 | ||
| Secondary | 42.7 | 44.7 | 55.8 | 39.5 | 48.6 | 43.7 | ||
| 1–3 Years’ higher education | 11.2 | 14.5 | 10.5 | 7.9 | 6.2 | 11.4 | ||
| ⩾4 Years’ higher education | 8.4 | 8.3 | 9.3 | 6.6 | 8.2 | 8.2 | ||
| Mean age at HUSK | 42.73 | 42.89 | 42.95 | 42.39 | 42.73 | 42.85 | p = 0.128 | – |
| Mean age at disability pension | 47.79 | 45.45 | 44.08 | 42.43 | 41.34 | 39.04 | p<0.001 | – |
| Physical diagnoses (z score) | −0.08 | −0.06 | −0.01 | 0.15 | 0.15 | 0.07 | – | p = 0.555 |
| Prescribed medication (z score) | −0.12 | 0.02 | −0.07 | 0.10 | 0.18 | 0.09 | – | p = 0.788 |
| Blood pressure (z score) | −0.02 | 0.06 | −0.08 | 0.10 | 0.00 | −0.04 | – | p = 0.509 |
| Pain distribution (z score) | −0.12 | 0.11 | 0.25 | 0.21 | 0.07 | −0.16 | – | p<0.001 |
| Somatic symptoms (z score) | −0.11 | 0.02 | 0.41 | 0.20 | 0.07 | −0.16 | – | p<0.001 |
| Anxiety symptoms (z score) | −0.08 | −0.01 | 0.23 | 0.16 | 0.03 | −0.03 | – | p = 0.047 |
| Depression symptoms (z score) | −0.15 | 0.07 | 0.21 | 0.23 | 0.03 | 0.01 | – | p = 0.016 |
| Sleep problems (z score) | −0.20 | 0.00 | 0.51 | 0.32 | −0.11 | 0.18 | – | p<0.001 |
*Significance tested with t tests for continuous measures and χ2 for categorical measures.
†p Values for the time-by-time interaction term in predicting each variable in linear regression.
HUSK, Hordaland Health Study 1997–1999; Sig., significance.